Norton 66243529777 Internal Grinding Wheel 60 Grit

Product Description

The NORTON 66243529777 is a Type 1 internal grinding wheel designed for precision bore and internal diameter grinding operations. Built with aluminum oxide abrasive in a medium grade, 60-grit specification, it delivers consistent stock removal on ferrous metals and tool steels. The vitrified bond provides rigidity and open porosity for cool, free cutting action. At 4 inches in diameter with a 1/4-inch thickness and 1/2-inch hole, this wheel is sized for internal grinding spindles and is rated to a maximum of 6,210 RPM. Machinists and tool grinders install this wheel on ID grinding machines for finishing bores, valve seats, and cylindrical internal surfaces.

This wheel suits production and maintenance grinding environments where bore tolerances are critical. Its medium-grade, semi-friable aluminum oxide construction makes it appropriate for general-purpose internal grinding on hardened steel, cast iron, and similar ferrous materials. The vitrified bond resists heat buildup and maintains wheel form throughout the cut, which is important for holding dimensional accuracy in tight-tolerance bore work. Typical applications include repair shops, tool rooms, and light manufacturing where internal surface finish and size control are required.

Key Features

• 60-grit medium-grade aluminum oxide abrasive for balanced cut rate and surface finish
• Vitrified bond construction provides rigidity and maintains wheel shape during internal grinding
• Semi-friable grain structure supports cool cutting and self-sharpening behavior
• Type 1 straight wheel profile fits standard ID grinding spindle configurations
• Rated to 6,210 RPM maximum for safe operation on compatible internal grinding machines
• White wheel color aids visual inspection for loading and glazing during use

Compatibility

Designed as an OEM-style replacement or standard consumable for internal grinding spindles accepting a Type 1 straight wheel with a 1/2-inch arbor hole and up to 4-inch diameter capacity.

Installation Notes

Internal grinding wheels must be installed by qualified machinists or grinding machine operators following the machine manufacturer's mounting procedures. Always power down and lock out the grinding machine before mounting or dismounting any wheel. Inspect the wheel for cracks or chips before mounting and perform a ring test per ANSI B7.1 standards. Never exceed the 6,210 RPM maximum speed rating marked on the wheel or its packaging.